This invention relates in general to electric powered work assist vehicles that are particularly useful in transporting items retrieved from shelves in a warehouse, or as a work platform which allows an operator to be raised approximately six feet or more from a floor of a work area and, more particularly, to such a vehicle having a weight sensor assembly for detecting if someone or something is located on a portion of the vehicle beneath a vertically movable passenger compartment.
Small parts picking is currently done by personnel manually pushing carts equipped with several shelves and a low level ladder which the operator climbs for reaching stock items up to nine feet high. Higher elevation picking, up to twelve feet, is accomplished with large manual push-in-place mobile ladder stands. Both the carts and mobile ladder stands require the operator to climb up and down while manually holding the goods.
A compact aerial lift vehicle which can be used for parts picking is disclosed in U.S. Pat. No. 5,273,132. The vehicle is separable into several parts for storage and can be controlled by an operator supported upon a platform which can be elevated along a vertical post member removably mounted upon a body of the vehicle. There is no provision for preventing the platform from being lowered onto someone or something located on the body beneath the platform. Such action can injure or damage whatever is on the body or cause harm to the platform and/or the vehicle body if the platform is allowed to be lowered. Injury, damage or harm can also result if the vehicle travels in this situation.
Accordingly, there is a need for an improved work assist vehicle which includes means for detecting if something or someone is located on a portion of a body of the vehicle.